Comments:

The DOS-standard emulating entities of SWSUBST, SUBST and JOIN, have
the same command line as DOS's have. But they differ in the following
points:
- The specified path will be make'ed, including the full path to it,
e.g. "SUBST c: d:/blah/humpf" creates the path "d:\blah\humpf",
regardless if d:\blah exists.
- You are allowed to break off relations on the fly, that means:
an already SUBST'ed can be re-SUBST'ed or re-JOIN'ed without
further note/warning.
- You are allowed to process a drive with itself, e.g.: "JOIN a:
a:\blah"
- The table dump is different, swsubst prints "X: => Y:\PATH" instead
of "X: is joined to Y:\PATH".
- You cannot rename the executables SUBST and JOIN.
- It won't test the DOS version, unless it's necessary for adjusting
different data structure sizes.
If you need SUBST or JOIN simply execute: "copy SWSUBST.EXE SUBST.EXE".
An ERRORLEVEL between 65 (ASCII 'A') and 90 (ASCII 'Z') indicates OK
and the drive letter itself; whereas an ERRORLEVEL of zero indicates,
that there is no such drive; and other ERRORLEVELS indicate an error.

See also:

File:

Please read this command's lsm file also.
You will find the updated version (internet) here and
the version described in this manual page here.
The lsm file contains information about the name of the programmer,
the download site, and some other command related information.